JPS62257181A - Color and black-and-white copying machine - Google Patents

Abstract

PURPOSE:To eliminate deviation among respective colors during color copying operation by arranging a black development unit at the part of one of three photosensitive body belt which differ in peripheral length and providing a movable optical path changing member so that only image light is projected on only the photosensitive body belt where the black development unit is arranged. CONSTITUTION:The black development unit 3 is arranged at the part of one of the three photosensitive belts 1Y, 1M, and 1C which differ in peripheral length, total reflecting mirrors E and F are constituted in blocks on the optical path 11 of exposure on the photosensitive body belt where the black development unit 3 is arranged, and the optical path change member 12 which equalizes its optical path length to the optical path length of the same photosensitive body irradiation at the time of full-color copying operation is provided movably. Then, a transfer conveyor belt 10 which conveys copying paper does not contact photosensitive body belts except the photosensitive belt where the black development unit 3 is arranged during black copying operation. Consequently, when the full-color copying operation is changed to black copying operation, none of color separation filters is moved, so there is no position shift of the superposition of the respective colors at the time of the full-color copying operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a copying machine having a three-photoconductor configuration and capable of making full-color copies and black copies.

[Prior art] There are two types of color copying machines: one with a photoconductor configuration and one with a three-photoconductor configuration;
When creating images (yellow, magenta, cyan), since the photoreceptor is common, a changeable color separation filter is installed at one point in the exposure optical path, and the light irradiated to photoreceptor 1 is changed each time it is irradiated. . When making black and white copies, it is only necessary to remove this filter, and it is relatively easy to construct a color/monochrome copying machine with a single photoreceptor configuration in terms of equipment and technology.
Color copying speed was slow, making it unsuitable for high-speed copying. In addition, although a color copying machine with a three-photoconductor configuration can speed up copying, if a filter is installed for both black and white copying, there will be a misalignment in the overlapping positions of each color during transfer to each photoconductor, resulting in high quality. I couldn't get an image.

[Purpose] Therefore, the present invention provides a full-color copying machine with a three-photoconductor configuration that has a simple configuration for switching between color copying and black copying, and can also perform black copying without causing misalignment of each color during color copying. This is what we provide.

[Structure] In the present invention, a black developing unit is juxtaposed to one of three photoconductor belts having different circumferential lengths, and a plurality of The total reflection mirror is configured as a block, and the optical path changing member is movably provided so that the optical path length is the same as the optical path length of the same photoreceptor irradiation during full color copying, and the transfer conveyance belt that conveys the copy paper is At one time, the photoconductor belt 1 other than the photoconductor belt on which the black developing unit is installed in parallel
This is a color/monochrome copying machine that is configured so that it is in a non-contact state.

[Example] Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of a copying machine incorporating the present invention, and FIG. 2 is a partial cross-sectional view of a copying machine for monochrome copying.

The copying machine has photoreceptor belts lY and 1M for three colors: Y (yellow), M (magenta), and C (cyan).

ICs are arranged in parallel, and Y(
A (yellow) IJl image unit l-2, a B (black) developing unit 3, and a cleaning unit 6 are arranged side by side.

An M (magenta) developing unit 4 and a cleaning unit 7 are juxtaposed around the photoreceptor pel 81M, and a C (cyan) developing unit 5 and a cleaning unit 8 are juxtaposed around the photoreceptor belt 1C. The circumferential length of the photoreceptor belt increases in the order of photoreceptor belt IY < photoreceptor belt IM < photoreceptor belt Ic, and the copy paper is fed from the paper feed cassette 9 on the yellow photoreceptor belt IY side and transferred. A full-color copy can be made by passing the paper once over the conveyor belt IO from the photoreceptor belt IY in the direction of the photoreceptor belt LC. In the middle of the exposure optical path 11, there is an optical path changing member 1 including total reflection mirrors D, E, and F as an integral block.
2 is appropriately arranged so that it can be moved diagonally downward to the right from the state shown in FIG.

First, the mechanism for making full-color copies using this copying machine will be explained.

First, the developing member such as the sleeve of the B (black) developing unit 3 is brought into a non-contact state with the photoreceptor belt IY, and the developing member of the Y (yellow) developing unit 2 is brought into contact with the photoreceptor belt IY.

The light passing through the imaging lens 13 includes light in the entire visible light range, and the blue light is reflected by the blue reflection filter 14 and irradiated onto the photoreceptor belt IY, forming a latent image on the surface of the photoreceptor belt IY.

Light with a longer wavelength than the green light passes through the blue reflection filter 14 and reaches the green reflection filter 15, and the green light is reflected by the filter 15 and irradiated onto the photoreceptor belt LM, forming a latent image on the photoreceptor belt 1M. form. The red light passing through the green reflection filter 15 is reflected by the total reflection mirror 16 and irradiated onto the photoreceptor belt IC, forming a latent image on the surface of the photoreceptor belt IC. The latent image on each belt is i1. ．． Y (yellow) developing unit 2, M (magenta) T! Each color is developed by an AI unit 4 and a C (cyan) developing unit 5, and then moved to the positions of transfer chargers 17Y, 17M, and 17c, where the three colors are transferred onto passing copy paper. The copy paper on which the transfer has been completed is sent to the fixing unit 18, and the copy paper on which the full-color copy has been completed is stacked on the paper discharge tray HIJ:.

Next, the mechanism for making a black copy will be explained (see FIG. 2).The black copy is imaged using only the photoreceptor belt IY and the B (black) developing unit 3.

First, the developing member of the B developing unit 1-3 is brought into contact with the photoreceptor belt IY, and the Y developing unit 2 is left in non-contact. An optical path changing member 12 is provided in front of the blue reflection filter 14 in the exposure optical path 11. The light that has passed through the imaging lens 13 is changed its optical path to the blue reflection filter 14 and beyond by the total reflection mirror D of the optical path changing member 12, and is further changed to the total reflection mirror E.
, F so that the entire luminous flux is irradiated onto the photoreceptor belt IY. Also, transfer the transfer conveyance belt lO to the photoreceptor belt lO.
- No contact with IM, 1c. Photoreceptor belt IM, Ic
Only the photoreceptor belt lY is driven without driving the photoreceptor belt lY.

The total reflection mirror D, mirror E, and mirror F of the optical path changing member 12 irradiate the entire luminous flux of the light that has passed through the imaging lens 13 onto the surface of the photoreceptor bell 817 to form a latent image.

Developed by the B developing unit 3 and transferred to the transfer charger 17
Press Y to transfer to copy paper. The transfer conveyance bell 1-IO that conveyed the copy paper has the transfer charger 17M and the transfer charger 17C OFF, but the conveyance bell! - The charge in the transfer charger 17Y is removed by the charger 20, and the transfer belt is cleaned by the conveyor belt cleaning device 1\21, and the process proceeds to the next step.

When the light amount of the exposure lamp 22 for black copying is the same as that for full color copying, the process linear speed for black copying and color copying is changed. In this case, the process line speed can be approximately twice or more than that for color copying. If the process linear speed is not changed, provide an appropriate amount of light by installing a filter or lowering the lamp voltage.

In this embodiment, the photoreceptor belts other than lY are inactive, but the other photoreceptor belts IM and Ic are gI! When moving the transfer conveyor bell 1, if it does not affect the image.
-10 is in contact with the photoreceptor belt 1M, l (first
(state shown in the figure).

Further, the cleaning unit 1-6 can also be designed to have a larger capacity than the other cleaning units 7.8. When the black copy is completed, the optical path changing member 12 moves diagonally downward to the right from the position shown in FIG. 2 to a position above the Y developing unit 2, 8 and the developing unit 3, and is removed from the optical path and stored as appropriate.

Note that the optical path length of the optical path member 12 is designed to be the same as the optical path length of a full-color temporary blue reflection filter.

[Effect] When changing from full color copy operation to black copy operation,
Since each color separation filter does not need to be moved, there is no misregistration of the overlapping colors during full color copying, and high quality color copies can be obtained without deteriorating the quality.
In addition, even during black copying, it is only necessary to move the optical path changing member, and after inserting it into the exposure optical path, there is no variation in the optical path axis and there is little negative effect on the copied image.Furthermore, the optical path changing member is integrated with a total reflection mirror, etc. The block structure has advantages such as easy moving operations, and a multifunctional copying machine that can make two types of high-quality copies, full-color copies and black copies, can be obtained.

[Brief explanation of drawings]

1 is a cross-sectional view of a copying machine according to the present invention, and FIG. 2 is a partial cross-sectional view of a black copy machine. IY, LM, IC...Photoreceptor belt, 2...Yellow developing unit h, 3...Black developing unit 1~. 4...Magenta development unit +-. 5...Cyan developing unit. 10...Transfer conveyance belt. 11... Exposure optical path. 12... Optical path changing member. D, E, F... Total reflection mirror of optical path changing member, 13
...Imaging lens. 14...Blue reflection filter. 15...Green reflection filter. 16... Total reflection filter.

Claims (3)

[Claims] (1) In a color copying machine equipped with three photoreceptor belts with different circumferential lengths, a black developing unit is juxtaposed to one of the photoreceptor belts, and an image is formed only on the photoreceptor belt with the black developing unit juxtaposed. A color/monochrome copying machine characterized by being provided with a movable optical path changing member to enable light projection. (2) The optical path changing member has a block configuration of multiple total reflection mirrors, and irradiates the entire luminous flux that has passed through the imaging lens onto the photoreceptor parallel to the black developing unit. 2. The color/monochrome copying machine according to claim 1, wherein the optical path length is the same as the irradiation optical path length. (3) The transfer conveyance belt that conveys the copy paper is configured to be able to come into contact with and separate from a photoconductor belt other than the photoconductor belt installed in parallel with the black developing unit. Color/black and white copying machine.